ne of the
recurring attacks on evolution comes from those who find the notion of
random change distasteful. One of the more pernicious and persistent
claims is Fred Hoyle's oft-quoted comment that accepting that
evolution occurs by selection is like thinking that a 747 would result
if a hurricane went through a junkyard [Hoyle 1981]. Some writers on
evolutionary theory have not helped this misconception, although those
who repeat it are remarkably resistant to correction on the actual
claims made by scientific evolutionary theory. Others have dealt
elsewhere with the exaggerated claims about Lamarckian inheritance,
Hopeful Monsters, macromutation and dogs giving birth to cats. This is
a brief philosophical discussion of the notion of randomness and
chance in evolution.

Conclusions of this FAQ

Genetic changes do not anticipate a species' needs, and those changes
may be unrelated to selection pressures on the species. Nevertheless,
evolution is not fundamentally a random process.

The Idea of an Evolutionary Accident

Darwinism has long being interpreted as a view of nature as based
upon "chance". Ideologues have pounced on this to bolster their own
extra-scientific philosophies. The antiscientific Stalinist
perversion of genetics in the USSR in the 1940s known after its main
proponent as Lysenkoism is an example. In an attack on Darwinism,
Lysenko said:

"Such sciences as physics and chemistry have freed
themselves from chance. That is why they became exact sciences.

Animate nature was developed and is developed on a foundation of
the most strict and inherent rules. Organisms and species are
developed on a foundation of their natural and intrinsic needs.

By getting rid of Mendelism-Morganism-Weismannism from our
science we banish chance out of biological science.

We must keep in mind clearly that science is the enemy of chance."

[T D Lysenko, Aug 7 1948. Appleman 1970:559]

Mendel, Morgan and Weismann were the biologists who discovered
genes and mutation. Their work underpins modern biology and modern
evolutionary theory.

Lysenko's intuitions about chance in biology were so successful
that 20 million people starved to death as a result of his false
science applied to agriculture. With appropriate substitutions about
"kinds" and God's purpose for species, the statement could have been
made by a creationist.

Some modern evolutionary biologists do make much of chance. The
Nobel Prize-winning molecular biologist Jacques Monod wrote
[1972:114]:

The initial elementary events which open the way to
evolution in the intensely conservative systems called living beings
are microscopic, fortuitous, and totally unrelated to whatever may be
their effects upon teleonomic functioning.

But once incorporated in the DNA structure, the accident --
essentially unpredictable because always singular -- will be
mechanically and faithfully replicated and translated: that is to
say, both multiplied and transposed into millions or thousands of
millions of copies. Drawn from the realm of pure chance, the accident
enters into that of necessity, of the most implacable certainties.
For natural selection operates at the macroscopic level, the level of
organisms.

This conception of genetic changes as accidental and unique, about
which no laws may be formulated, is fundamentally flawed, for all
that it reappears in a number of influential works on evolution.
Causes of genetic change are being uncovered routinely, and they
involve better or worse understood mechanisms that are very far from
random, in the sense that there are very clear causes for the
changes, and that they can be specified in detail over general cases.
Monod's use of the phrase "realm of pure chance" is rhetoric and is
misleading at best, simply false at worst.

To make this clear, we need to see the general pattern of
evolution.

Bipartite Evolution

Darwin called his principle of the evolutionary process "natural
selection", a term that has given rise to almost as much confusion as
the malignant phrase donated to him by the philosopher Herbert
Spencer, "survival of the fittest". It has been understood to mean
that the natural world is an agent, selecting according to some
purpose or goal; that nature aims to perfect or complete the
potential of a species. Nothing could be further from the truth.

Natural selection in modern science is a feedback process.
It requires two "forces", as it were, one acting to faithfully (but
not quite perfectly) replicate the structure of the organism
(reproduction and ontogeny) and the other sorting the interactive
characteristics of organisms with the environment (the phenotype or
set of traits) into those more or less efficient at survival and
therefore at reproduction opportunities. A better term for it,
therefore, is "environmental sorting of
heredity", since it is the way in which certain traits equip
organisms that increases or decreases their chances at being passed
on, relative to other traits in that population of organisms.

Sober [1984:99] illustrates the process in this way: imagine a
child's toy that has numbers of three different size balls in a
container, with two internal layers that have increasingly smaller
holes in them. Shaking the toy (a randomising process) increases the
likelihood that the smaller balls will pass through the first filter,
and that the smallest balls through the second. The smallest balls
are, in effect, the most "fit" (or make the best fit) and make it
through to the bottom. There has been a selection, or sorting,
process which results in the smallest balls making it to the bottom.

The feedback loop in evolution results when the genetic structure
causes the phenotypic traits to develop (as opposed to when
there is no covariance between gross organismic traits and its
genotype, eg, acquired characteristics). Traits that are more
efficient than the alternatives available in the reproductive
population (called a 'deme' by Sewall Wright,
who proposed the process of genetic drift mentioned below)
have an increased likelihood of reproducing.

Darwin saw, from reading the 1798 Essay on Population by
Malthus, that if there are more descendents than can survive with the
environmental resources available, then the more efficient resource
users will increase as a proportion of that population, and the less
efficient decrease. If a breeding
population or deme is isolated from its related populations long
enough, then the traits in that deme that mark it out from other
closely similar demes will diverge too far from the ancestral
populations for interbreeding to occur. By that stage, the isolates
will have become a new species.

In any small deme, there is a finite
probability of any two organisms mating, and so the genetic makeup of
the deme as a whole can lose and spread genes differently to the
'parent' population. In this way, also, the isolated population can
differ, and speciation occur. This is known as 'genetic drift' and is
a distinct process to natural selection.

Several important conclusions fall out from this way of modelling
change. For a start, the term "species" becomes more fuzzy. There are
no hard and fast boundaries between a parent species and its child
species; at least, not at first. There is a clear boundary between a
cat and a dog. There is a fuzzy boundary between a horse and a
donkey, which can breed (but their progeny, the mule, is not
fertile). Other species, such as zebras and horses, or lions and
tigers, can interbreed and their progeny are sometimes
fertile. "Species" becomes partly a
taxonomic term of convenience rather than a metaphysical kind or
class. Incipient species can be termed "varieties" or "subspecies" or
even "races", and biologists nowadays tend to award species rank only
when interbreeding is either behaviourally or
genetically difficult. Many species of bird are distinct primarily in
their mating behaviour, even though they are interfertile, as is the
case with lions and tigers. The fact that they do not
interbreed marks them as distinct species (this
is called the Biological Species Concept).

Another conclusion to be drawn is that there is no set goal to
selection. Variants arise naturally in all populations. Each
population has its traits spread out over a
distribution curve. While quadrupeds generally do not give
birth to viable three legged individuals, legs can be longer or
shorter, and whichever trait confers advantage at the time is the one
which will be more widely reproduced. Given that resources are
limited (or scarce, in Darwin's terminology) if for example longer
legs give an advantage in survival over
shorter legs, then the mean length of legs in that population will
increase, and eventually take over ("go to fixation") in the absence
of any other changes of environment. This does not happen because
longer legs are in any eternal way more "perfect", but rather because
they are more adequate for the tasks at hand of
simply making a living long enough to reproduce. "Survival of
the fittest" should be rephrased as "survival of the more adequate".

Sidebar: The terms "replicators" and
"interactors" are due to R Dawkins and D L Hull (a biologist
and a philosopher) and is now referred to as the
Hull-Dawkins distinction [Dawkins 1977, 1986, Hull 1988, cf
Williams 1992]. Note that under this general
characterisation, the term "resources" includes access to
mating opportunities, and so sexual selection is a subset of
"natural" selection.

The fact that environmental sorting occurs
with living organisms sometimes blinds us to the fact that it can
occur with other sorts of things. The general conditions for a
Darwinian process are merely that there is a definite structure that
gets replicated, which causes features that result in differential
success at gaining resources, and that those resources are in turn
what is required for replication to occur. Hence the feedback loop:
replicators to interactors to replicators.

The heirarchy of effects of replication (gamete or germ cell, to
zygote, to infant, to adult) and the hierarchy of interaction (access
to food, selection of mate, reproduction and parenting) work in
tandem as a cycle. Lewontin [1974] drew the process as a wave, which
I adapt here:

where L1 is the set of processes, or laws, that regulate
fertilisation, L2 the laws that regulate ontogeny (development of the
fetus), L3 the laws that regulate individual growth and survival, and
L4 the processes of mating and fertilisation. The Economic domain
represents the broader environmental end of the spectrum, and The
Codical domain represents the genetic environment.

This is not just restricted to biological change. "Darwinian"
models have been developed to cover the replication of social
phenomena (eg, Dawkins [1984], Cavalli-Sforza and Feldman [1981],
Rindos [1984], Hull [1988], Plotkin [1994], Richards [1987]) and the
so-called "genetic algorithms" now used in computer science to solve
problems of large scale phenomena use formally identical steps. A
generalised Darwinian process is one that has populations of
interactors that replicate, and in which replication is causally
correlated with interactive traits.

The Rules of Life

Some changes to genes involve mixing (say, between parents)
according to well-understood principles of population and molecular
genetics. Other changes involve chemical processes that interfere
with the transcription of DNA to proteins, that cause (again, in
accord with the principles of organic chemistry) mistranscriptions
either at replication or at conception. Let's call these
Replication Rules, the L1 processes of Lewontin's diagram
above. "Random" in the sense of there being no causal process that
determines the eventual genetic outcome, does not describe any event
that occurs at any stage in replication.

Once a change has been caused, by whatever process, that change enters
into the process of transcribing DNA into a phenotype (the structure
of the organism). This is the process of production of the juvenile
organism, known in animal biology as ontogeny, or
development. [Analogous processes occur in other kingdoms, such as
plants, but it does not pay to either be too literal, or to think that
what is true of animals (especially of mammals) is therefore the model
of what is true of all life.] The transcription of these proteins
results in cellular structures that then develop into an organism in a
process of differentiation and specialisation of cell reproductive
lineages, resulting in skin, skeletal structures, organs, etc. These
processes (L2 in the diagram) follow what we shall call Development
Rules.

Finally, the resultant phenotype, or organism, is then a part of
its ecology, attempting to gain a share of the resources it needs
(food, mates, space) in competition with other organisms that also
seek these resources. This includes predators, who want the resources
of the organism's bodily organic chemistry. The rules that cover this
sphere (L3 and L4 in the diagram) we may call Ecological
Rules, and they cover also mating behaviour in species that mate.

Natural selection, including sexual selection, is a sorting or
filtering process that occurs when variants caused by Replication
Rules do better at survival under Development Rules and Ecological
Rules than other variants in competition for ecological resources, and
which replicate more frequently than those competitors. [This
definition is very broad on purpose, for it includes both competition
for food and other resources within a species and interspecific
competition for survival; say, between predator and prey.]

Now, under most interpretations of scientific law, the sorts of
rules that Replication Rules are, are definitely scientific laws
[cf Ghiselin's and Thompson's essays in Ruse
1989]. Not too much rides on the form of this, though, for it
is enough to say that explanations of DNA and RNA transcriptions are
causal chains, and are therefore scientific explanations in the true
sense: they explain what causes the outcomes from the initial
conditions and the properties of the objects involved.

There is no basic randomness here, except as far as it arises from
the general indeterminacy of the physical world (known as stochastic
processes). The same is true for Development Rules. Fetal development
in mammals is becoming well understood in terms of the causes of cell
differentiation and gene activation. Once these processes have been
fully uncovered, there will be no randomness here, either.

Therefore, randomness must enter into evolution per se, if it does, at the level of
Ecological Rules; that is, in the ecological struggle [Sober 1984].
However, nobody can fairly argue against the statement that certain
phenotypic properties -- a longer beak or stronger hindlegs -- can
influence their relative reproduction in a population. So, even if
the correlation is only a matter of frequency, there is still a
nonrandom relationship between what is claimed as the cause and the
effect.

Yet, it is often claimed that randomness drives evolution, as in
the quotation from Monod above. We have to ask,
where does chance really enter into evolution?

Random Relative to What?

To understand the randomness claimed for evolution by scientists,
as opposed to that feared by theologians and moral philosophers, it's
important to ask "random relative to
what?" In any model of a process as described by a scientific theory,
there are many things taken for granted. Philosophers of science
refer to these as ancillary assumptions or hypotheses. Some of these
are assumed from ignorance: science might not yet have any workable
and tested theory or model to deal with that class of phenomena.
Others are assumed because they are well worked out in another
scientific theory or discipline.

For example, Darwin knew that there was heredity, but he
did not have a good theory of heredity to work by. His selection
theory (the version he and Wallace published) had to assume that
traits were heritable. He did propose a theory of heredity
(pangenesis) based on a now discredited view of the influence of the
use of traits on reproduction, but it was never essential to the
theory of natural selection. So far as his theory of evolution by
selection was concerned, heredity was an area to be filled out later.

Once Mendel's principles of heredity were rediscovered, permitting
mathematical models of genetic change at the level of populations to
be formulated by Haldane, Fisher and Wright and others in the 1930s
and 1940s, the so-called Neo-Darwinian ("synthetic") theory of
natural selection used these results as ancillary hypotheses. Added
to this Weissman's germ plasm theory that the sex cells (the "germ
plasm") were not "reverse programmed' by the phenotypic organism (the
"soma"), and natural selection of
genetic content became a one-way causal process. Genes cause the
ecologically active phenotype, but the phenotype does not program the
information content of the genes. Hence, relative to natural
selection, genetic content changes are "random". Let's call this the Black Box Conception of
Randomness [See Bowler 1983 on the history of post-Darwinian
theory and Dawkins 1996 for a fuller development of this.]

Another way to say this is just that the changes that get encoded
in genes occur with no forethought to the eventual needs of the
organism (or the species) that carries those genes. A gene change
(for instance, a point mutation -- a mistake at a single locus of the
genetic structure) may change in any way permitted by the laws of
molecular biology, according to the specific causes at the time. This
may result in a phenotypic change that may be better suited to
current conditions than the others about at the time. However, it
probably won't. So far as the local environment is concerned, the
change is the result of a random process, a
black box that isn't driven with reference to things going on at the
level of the environment. It's not really random, of course,
because it is the result of causal processes, but so far as natural
selection is concerned, it may as well be.

Replication Rules must involve what Dawkins calls "high fidelity"
replication. Too high a rate of error would introduce too much
"noise" into the replication process for selection to work
effectively. Error rates in replication are indeed very low ("Typical
rates of mutation are between 10-10 and 10-12
mutations per base pair of DNA per generation",
Chris Colby's Introduction
to Evolutionary Biology FAQ). Each error is the result of purely
physical processes and can at the micro level be theoretically
predicted, although in the real world we could never predict the
sorts of mutations and transcription errors that will result for any
particular case, from a lack of
information.

Replication Rules are not random in the sense that, say,
Heisenberg's Principle of Uncertainty or quantum mechanics is
sometimes supposed to show the fundamental randomness of reality.
They are merely random with respect to natural selection.
Natural selection is not random: it is the determinate result of
sorting processes according to relative fitness. It is
stochastic, in the sense that better engineered features can fail for
reasons of probability (they may meet accidents unrelated to their
fitness), but that poses no greater threat to the scientific nature
of evolution than it does for, say, subatomic physics or information
theory.

There are scientists and philosophers who think that probabilities
represent a real indeterminacy in the world; that even if you had, in
principle, full information about all causes for a system, it would
still be possible only to predict the distribution curve rather than
the outcome for any single object. This is called the
propensity interpretation (Beatty and Finsen in Ruse 1989), and
holds that real things have a real propensity to behave in a range of
ways rather than a real set of properties that will specify a strict
determined outcome. Whether this is true or not is not relevant to
evolution as such, for if it is true, then it is true of
everything, and not just living things.

Different Senses of Chance

We need to distinguish between two senses of "random": the one
kind that involves a total break in the causal chain, and in which
the event is essentially chaotic; the other that requires only
unpredictability, such as the decay of unstable atoms, or Brownian
motion, but which remains a caused event. These get confused all the
time. There is nothing about changes in a genome or a gene pool that
is random in the first sense, but much of the second sense. For
example, shuffling a deck of cards results in a properly physical
process of the rearrangement of each card, yet there is no real way
to predict the order of a random shuffle. Cards don't just
materialise in place, but you don't know what you will end up with
(unless you bias the shuffling so it isn't random).

Gould [1993: 396f] has written about the different senses of
"random" and "chance" in science:

"In ordinary English, a random event is one without
order, predicatability or pattern. The word connotes disaggregation,
falling apart, formless anarchy, and fear. Yet, ironically, the
scientific sense of random conveys a precisely opposite set of
associations. A phenomenon governed by chance yields maximal
simplicity, order and predictability--at least in the long run. ...
Thus, if you wish to understand patterns of long historical
sequences, pray for randomness."

Why is this? It has to do with the nature of explanation. An
explanation is an answer to a set of questions about something that
presents a problem. Historical explanations deal with long and
complex processes, with causes that continue back to the beginning of
the universe, and are known as etiologies, from
the Greek aitos, for 'cause'. Where does an etiological explanation stop? In science,
explanations have to deal with phenomena in their own terms, dealing
with the properties of the things being explained. Evolution through
natural selection deals with the changes of organisms through time.
The causes of mutations are not evolutionary processes; the changes
to organisms that result from mutations are. In other words:
given that organisms accrue different traits (from whatever
causes, and which we now know are mutations) evolution is the result
of these in terms of ecological benefits.

Consider an explanation of a falling object's trajectory. Newton's
laws show that without such things as air friction or rocket exhaust
an object falls in a parabola. Yet no object in the existence of the
universe has fallen in a mathematically precise parabola. Gravitation
from distant objects, winds caused by the weather on a specific day,
and friction on irregular surfaces all affect any real trajectory.

A full explanation of the path taken by the cup of coffee
my cat knocked onto the floor the other day nees to deal with the
history of the manufacture of the cup, the physiology and psychology
of the cat, the historical circumstances whereby the cat and cup came
into contact, and so forth back to the big bang. Such an explanation
is humanly impossible.

These things are "contingent". Contingency is a technical term
used in philosophy and science to label things that are "inessential"
to the explanation. There are too many things to be explained, and in
any event they do not really affect the efficiency of the
explanation. Some things one can take for granted, other things just
don't make a significant difference.

Gould has written that if we could rewind the "tape" of evolution
and replay it, the result would not be the same (Gould 1989). Among other things, humans are
almost certain not to re-evolve. This is because the number of
contingent causes (asteroids hitting the earth, continental drift,
cosmic radiation, the likelihood of significant individuals mating
and producing progeny, etc) are so high that it is unlikely they
would occur again in the same sequence, or even occur at all. If an
asteroid hadn't hit the Yucátan Peninsula 65 million years
ago, for example, mammals probably would never have diversified, as
they didn't in the 100 million years before that.

Processes explained by science are affected by their intrinsic
properties, the initial conditions and the boundary
conditions. The cup fell from 1 meter. That's an initial
condition. There was no real wind, but there was air friction. Those
are boundary conditions. The cup had a certain mass and fell in a
gravitational field of 1g. Those are the intrinsic properties.
These last are not explained by Newtonian physics, but by
Einstein's physics of time and space.

Contingent events are sometimes exceedingly
sensitive to the initial conditions. A single slight difference can
lead to a radically different outcome. If the cup fell from one meter
but into the folds of a rigid tablecloth (a boundary condition), then
a millimeter of difference in the way it fell (in its initial
conditions) could leave it in pieces on kitchen floor, or in the
dog's sleeping basket and safe, though in need of a wash.

Evolutionary theory explains why objects with certain properties
move and change the way they do: how organisms change over time. In
evolution, the initial and boundary conditions are contingent. That
is the extent, the whole of it, of randomness and chance in the
history of life.

Fear of the ordinary sense of chance and random which Gould
describes above arises largely from a desire to find meaning in the
events of the world around us. Science is not the appropriate place
to find this meaning. Neither can meaning be imposed upon scientific
explanations. Attempts to impose preconditions on science can have,
as they did in the case of Lysenkoism, dire consequences, and at the
very least they impede science in its search for adequate
understanding of the world around us.

Some Final Words from the Professionals

Since the first version of this essay, Dawkins published his 1996.
Since Dawkins is sometimes represented denying
any role in evolution for chance
at all, I profer the following
quotations:

It is grindingly, creakingly, obvious that, if
Darwinism were really a theory of chance, it couldn't work. [Dawkins
1996: 67]

Darwinism is widely misunderstood as a theory of pure chance.
Mustn't it have done something to provoke this canard? Well, yes,
there is something behind the misunderstood rumour, a feeble basis to
the distortion. one stage in the Darwinian process is indeed a chance
process -- mutation. Mutation is the process by which fresh genetic
variation is offered up for selection and it is usually described as
random. But Darwinians make the fuss they do about the 'randomness'
of mutation only in order to contrast it to the non-randomness
of selection. It is not necessary that mutation should be
random for natural selection to work. Selection can still do its work
whether mutation is directed or not. Emphasizing that mutation
can be random is our way of calling attention to the crucial
fact that, by contrast, selection is sublimely and quintessentially
non-random. It is ironic that this emphasis on the contrast
between mutation and the non-randomness of selection has led people
to think that the whole theory is a theory of chance.

Even mutations are, as a matter of fact, non-random in various
senses, although these senses aren't relevant to our discussion
because they don't contribute constructively to the improbable
perfection of organisms. For example, mutations have well-understood
physical causes, and to this extent they are non-random. ... the
great majority of mutations, however caused, are random with respect
to quality, and that means they are usually bad because there are
more ways of getting worse than of getting better. [Dawkins
1996:70-71]

Dawkins both accepts the role of chance in evolution through
mutations and denies, as this FAQ does, that evolution thereby
involves deep improbability. The 'quality' he speaks of is what gets
selected by natural selection sorting processes.

And to show that Dawkins's views are not
just modern revisionism, the final explication must go to GG Simpson,
in 1953 (pages 86f):

... the effects of any one
mutation are limited by the existing gene (or reaction) system in
which it occurs. A more profound reorganisation is required to make
possible other directions of mutational change.

This sort of limitation and the fact that
different mutations may have widely and characteristically different
rates of incidence show that mutations are not random in the full and
usual sense of the word or in the way that some early Darwinists
considered as fully random the variation available for natural
selection. I believe that the, in this sense, nonrandom nature of
mutation has had a profound influence on the diversity of life and on
the extent and character of adaptations. This influence is sometimes
overlooked, probably because almost everyone speaks of mutations as
random, which they are in other senses of the word.

There is, on one hand, a randomness as to
where and when a mutation will occur. ...

On the other hand, the term "randomness" as
applied to mutation often refers to the lack of correspondence of
phenotypic effect with the stimulus and with the actual or the
adaptive direction of evolution. ... It is a well known fact,
emphasized over and over again in discussions of genetics and
evolution, that the vast majority of known mutations are inadaptive.
...

A population in process of adapting to
chnage in its environment or to an environment new to it may be
expected to have some adaptive instability. It may be adapting by
utilization of expressed and potential variability but it may also be
adapting in part by adaptive mutations. Sooner or later and in some
changes of adapation, if it is true that mutation is the ultimate
source of material for evolution, adaptive mutation must be involved.
In spite of the general "randomness" of mutation in the special
senses noted, there is adequate evidence that aadaptive mutations are
often available under such circumstances.

Things have dramatically empirically
improved in the last 40 or so years, but Simpson's points remain as
valid now as they were then.

Bowler PJ The Eclipse of Darwinism: Antievolutionary Theories
in the Decades Around 1900 Johns Hopkins 1983

A fascinating account of the way Darwinism was largely
abandoned at the turn of the century, especially showing how many of
the objections from antievolutionists today to Darwinism were first
raised then and how they were dealt with. Should be required reading
for creationists and Lamarckians.

An attempt to apply the mathematical equipment of
genetics to cultural phenomena. The first author has since extended
his work to North American indigenous languages, rather
controversially.

Dawkins R The Selfish Gene Oxford UP 1977 (1989 edition)

The book that started the popular debate on "selfish
genes". Dawkins based his book on the previous work of G C Williams,
but used aggressive language to argue that the only accurate
perspective to view evolution from is that of the gene. He probably
now regrets his use of voluntarist language (ie, using terms like
"selfish", "act" etc of genes), since it has given rise to so much
misunderstanding, from the wilful to the pig-ignorant. NB: This is
not sociobiology.

Dawkins R The Blind Watchmaker Longman Scientific and
Technical 1986

A very clearly expressed argument that design is not a
part of the natural biological world, in opposition to Paley's
Natural Theology (1802). As Terry Pratchett has expressed it,
bad design is evidence of a blind watchmaker.

Dawkins R River out of Eden Weidenfeld and Nicholson 1995

Dawkins reprises some of the arguments of the above
books and in the final chapter discusses the "Utility Function"
maximised, either by God or blind selection, in the biological world.
He plumps again for the continuity of genes, but in this book, the
voluntarism of the Selfish Gene is muted. By far the most
readable of a very readable author's popular works.

Dawkins R Climbing Mount Improbable Viking Press 1996

This is Dawkins' most comprehensive account of why
evolution is neither a chance result nor a dramatically improbable
sequence of large scale changes. More than any of his other books, he
deals with the common misconceptions of creationist and
anti-evolutionist arguments. Chapters cover spider webs, flight, the
evolution of the 40 or so eyes that have independently arisen,
shells, embryology, insect-plant coevolution, and of course, chance.

Gould SJ Wonderful Life: The Burgess Shale and the nature of
history Penguin Books, 1989

This book caused a lot of
debate, as Gould's books often do, about contingency in evolution,
arguments that are still being carried on. Despite some of the more
dramatic claims about the distinctiveness of the fauna of the Burgess
Shale being recently revised, the major thesis is still
relevant.

I ought to point out that Hoyle was commenting upon
the chance formation of proteins, referring to abiogenesis, but the
comment bears on natural selection in general. Dawkins 1996:90 says
this:

"He [Hoyle] is reported to have said that the evolution, by
natural selection, of a complicated structure such as a protein
molecule (or, by implication, an eye or a heart) is about as likely
as a hurricane's having the luck to put together a Boeing 747 when
whirling through a junk yard. If he'd said 'chance' instead of
'natural selection' he'd have been right. Indeed, I regretted having
to expose him as one of the many toilers under the profound
misapprehension that natural selection is chance."

Hull D L Science as a Process: An evolutionary account of the
social and conceptual development of science U Chicago P 1988

A complex and interesting pot pourri of matters
evolutionary. The central thesis is that science is itself an
evolutionary process driven by a Hamiltonian "conceptual inclusive
fitness", or desire for credit. Has an insiders' view of the
cladist/pheneticist debates of the 60s. A very
interesting discussion of the nature of species is included, along
with a potted history of many concepts and theories in biology. An
influential book (see Ruse 1989).

Lewontin R The Genetic Basis of Evolutionary Change
Columbia UP 1974

A standard reference on the topic.

MacKay D M Science, Chance, and Providence Oxford UP 1978

MacKay discusses how events which are fundamentally
unpredictable from human perspective (e.g. the outcomes of quantum
measurements) need not be undetermined from God's perspective.

MacKay D M The Open Mind and Other Essays Inter-Varsity
Press 1988

Contains most of the content of Science, Chance,
and Providence, and is more widely available.

Mayr E 1988 Toward a New Philosophy of Biology: Observations of
an evolutionist The Belknap Press of Harvard UP

Mayr's main arguments have to do with the nature of
teleological explanation in biology and the nature of species. He
also presents a case that evolution presents a new philosophical and
methodological mindset (just as Newtonian theory had for Kant) which
he terms (dysphoniously) "population thinking" (there has to be a
pretentious classical or German neologism for this).

Monod J Chance and Necessity Collins 1972

This is well-known and thought-provoking, but
ultimately overdrawn, as so often is the case when a scientists steps
outside the specific discipline from which their reputation proceeds.
The theme is that we are thrown into some sort of Sartrean void
because there is no meaning to evolution.

Plotkin H C Darwin Machines and the Nature of Knowledge:
Concerning adaptations, instinct and the evolution of
intelligence Penguin 1994

A clear and readable presentation of the view that not
only is all knowledge an adaptation (to the selective pressures of
reality) but that all adaptations are in a real sense knowledge.
Written by a leading psychologist/philosopher.

Polkinghorne J C Science and Providence Shambhala
Publications 1989.

Polkinghorne discusses how modern understandings of
"chaos" allow the possibility for God to affect the outcomes of
"chance" events without contravening the ordinary laws of nature.

Written by an historian, presents the view that
historical processes may profitably be seen as Darwinian processes.
Has a good appendix on types of historical evolutionary theories,
including Kuhn and Merton.

Arguing that agriculture was a dual evolutionary
process: a sociological process involving cultural innovation and
dissemination; and a biological one involving the creation of many
new crop species through inadvertant selection at first and later
artificial selection.

For those wishing to get into
the detailed issues of philosophy, I recommend the essays by Beatty
and Finsen on the propensity interpretation, Cracraft, Ghiselin,
Kitcher, Mayr and Williams on the nature of species, and the more
evolutionarily pertinent pieces by Rosenberg on the nature of method,
Sober on systematics, and Wiley, especially for philosophical
creationists, on 'Kinds, Individuals and Theories'.

Simpson GG The Major Features of Evolution Columbia University Press, 1953.

A revised version of Tempo and Mode in Evolution, which
invented episodic evolution under the neo-Darwinian umbrella in 1943,
nearly 30 years before Gould and Eldredge. Anyone wondering what the
'synthetic theory' actually is would be well-advised to read
this book, at least as a starting point.

The text on matters such as "is Darwinism a
tautology?", "What is the unit of selection?", "Is Natural Selection
a scientific theory?". Argues that in evolutionary theory, selection
is a biological "force" or set of "forces".

Discusses in some technical detail the theoretical
issues of selection. Williams is responsible for demolishing group
selectionism, and showing that advantages accruing to a gene lineage
drive the broader evolutionary process of adaptation.